Adjustable clamping fixture for workbenches



V. SPINNLER April 6, 1948.

' ADJUSTABLE cmmrme FIXTURE FOR worm BENCHES Filed Sept. 13, 1944Patented Apr. 6, 1948 ADJUSTABLE CLAMPING FIXTURE FOR WORKBENCHES ViktorSpinnler, Zurich, Switzerland Application September 13, 1944, Serial No.55392.9

1 Claim.

The present invention relates to a clamp for-fixing work pieces of anykind, especially of wood, such as boards, fillets and the like, and anobject of the invention is, first, to provide a clamp with onestationary and one movable gripping jaw, and with a fixing deviceprovided with an eccentric clamping lever operated by Icanting, for thepurpose of locking the movablelclamping jaw'and thus clamping the workpiece between the two jaws; second, to provide means for a verticaladjustment by which the upper edge of the clamping jaws can be loweredto the level of the top of the work table; third, to provide a movabletool which may transform any plain table into a full joiners beach, thusrepresenting a perfect substitute for a planing bench.

The accompanying drawing illustrates two forms of construction:

Figure 1 shows a side elevation of the clamp mounted on a table topaccording to the first form of construction as seen in the direction ofthe arrow I of Figure 2;

Figure 2 is a top plan view of the clamp and table top shown in Figure1, seen in the direc tion of the arrow II of Figure 1;

Figure 3 is an end elevational view as seen in the direction of thearrow III of Figure 1;

Figure 4 shows a section on the line IV-IV of Figure 2, with the movableclamping jaw and lever in another position;

Figure 5 is a top plan view of a second form of construction of a holderfor the clamp having two clamp-guides.

In the construction shown in Figures 1 to 4, number I indicates astationary, preferable wooden, gripping jaw of a clamp. This clampingjaw has a downward extension 2 with a barlike carrier 3 fixed thereon bymeans of screws 4, said carrier being at right angles to the clampingjaw I and its extension. Number 5 designates the movable clamping jaw,likewise made of wood, said jaw being fastened through a screw 6 onto anangle iron I which is welded onto a sliding I 2 ture therein through ed,said aperture being provided with two tipping edges I4 and M located onopposite sides of said carrier and at' a, slight axial distance a fromeach other.

I5 designates a holder for the clamp, this holder possessing four lapsI6 and I1 intended for sliding over a table top I3. serve respectivelyfor loosening and tightening the clamp holder it on the table top I8.The holder I5 is provided with a guide-bed 20 for receiving theextension 2 of the clamping jaw I, said extension being verticallyadjustable in the guide-bed 2i and being adapted to be secured at anyposition of elevation by means of the clamping screw lever 2|.

The manipulation and function of the clamp is as follows:

First, the holder I5 is conveniently mounted on a table top I8,whereupon the extension 2 of the clamping jaw I is inserted into theuide-bed 20 of the holder I5 and tightened in the required verticalposition by means of the clamping screw lever 2|. The wooden work piece,for instance a plank 22, is then inserted between the jaws so that itrests simultaneously on the'table top l8. The support 9 with theclamping lever I0 is thereupon shifted from the position shown in Figure1 in the direction of the arrow III until the clamping jaw 5 liesadjacent the plank 22, whereupon the lever II] is moved in the directionof the arrow A indicated in Figure 1, thus forcing the jaw 5 away fromthe pivot of the eccentric I 2 of lever Ill, and pressing it in thedirection of the arrow III of Figure 1-firmly against the work piece 22.Due to the clamping pressure thus set up adverse to the direction ofarrow III, the support 9 on carrier 3 tilts, and owing to the onlyslight axial displacement a of the tipping edges the clamping pressureconveyed to the edges I4 and M is increased so as to causeself-impediment, the support being held fast, friction-tight on thecarrier 3. Since the eccentricity of the cocentric I2 is a comparativelyslight one, there likewise existsin the position of the eccentric asseen from Figure 4self-impediment between ec-' centric and angle iron Iso that the lever Ill, without further effort, remains locked in theposition shown in Figure 4. The work piece 22 is now tightly grasped bythe clamp on both sides with its edge resting on the table top I8, thusensuring a firm hold of the work piece. The work piece 22 can now, forinstance, be planed, sawed, drilled, polished, filed, rasped orotherwise along the bar-like carrier 3 by reason of an apertreated.

which the carrier is insert Two fixing I screws I 9 the work piece 22.

If the clamping connection is to be loosened again, the lever I israised opposite to the direction indicated by arrow A, the projection l2of the eccentric pushing against the pin l3 to cause a displacement ofslide 8 in the opposite direction of the arrow III indicated in Figure1, the clamping jaw being thereby withdrawn from The clamp-holder asshown in Figure 5 is provided with two guide-beds 20, 20' forselectively receiving the extension 2 of the clamp, the arrangement ofsaid guide-beds towards each other being such as to cause thelongitudinal axes (shown in Figure 5 by dash-and-dot lines) of the crosssections of the guide-beds to run at right angles to each other. If theclamp is set into the guide-bed 20' it can conveniently be used as an;

ordinary vise.

While I have herein illustrated and described certain preferredembodiments of the present invention, it will be apparent that changesin the construction and operation thereof may be made without departingeither from the spirit of the invention or its scope as claimedhereafter.

I claim:

An attachment of the character described com prising, in combination: aclamp including a stationary jaw having an extension arm, a carrier barextending laterally from the side of the'e'xtension arm adjacent saidstationary jaw, an adjustable mount having an aperture to receive saidcarrier bar therethrough and having tipping 4 edges on opposite walls ofsaid aperture adapted to effect locking engagement of said bar uponcanting of said mount, an engaging jaw disposed for limited slidingmovement along said mount, an eccentric locking device adapted to urgesaid slidable jaw against an engaged work piece and thereby cant saidmount upon said carrier bar, a clamp holder having means for attachmentto a table top and having a guide bedadapted to receive said clampextension arm t'herein, said guide bed having an upper edge disposedbelow said table top so that said jaws may be positioned substantiallyflush with said table top, and lockin-g means on said guide bed forsecuring said extension arm at selected positions of vertical adjustmenttherein.

1 VIKTOR, SPINNLER.

REFERENCES CITED The following references are of record in the fileofthis patent:

UNITED STATES PATENTS

